In a typical broadcast system, it is often desirable to combine the audio and/or video (“AV”) signals generated at multiple sources, such as video cameras, together at a common renderer, such as a computer monitor or other display. Additionally, it may be desirable to synchronize the display of an image from a source at a plurality of renderers. Conventional methods for accomplishing these goals have employed a variety of techniques. One such technique is known as GenLock. GenLock employs an external signal generator used to manipulate a plurality of AV sources to ensure those sources are transmitting the AV signals synchronized. For example, multiple cameras may be manipulated to ensure that each camera is transmitting video frames at the same time. Thus, GenLock requires manipulation at the source level of the AV transmission.
Conventionally, many multimedia communication systems employed imbedded networks for transmissions between a source and renderer. In recent years, however, it has become desirable for IP-based solutions to multimedia communications. Multimedia transmissions over an IP network will have significant advantages over conventional imbedded systems, including decreased cost of infrastructure, greater scalability, and greater routing capabilities. The introduction of IP based multimedia communication, however, leads to increased issues with latency. Latency can be defined as the delay between a change at the input of a system and the corresponding output of the system. For example, with video data transmissions, end-to-end latency can be the time between transmission of a video frame by a source and display of the frame by a renderer. The latency can be affected by many factors, such as processing speed and network delay. Many conventional systems attempt only to control latency by decreasing latency as much as possible. Unfortunately, these systems allow the display latency to oscillate, i.e. change frame to frame, throughout the data transmissions, leading to undesirable jitter in the display of the signal. This is especially problematic for applications where latency oscillation is unacceptable, such as in systems for conducting remote medical procedures.
Therefore, there is a desire for systems and methods for stabilizing the latency of a AV data transmission over an IP network, wherein the latency stabilization takes place substantially at the renderer level. Various embodiments of the present invention address these desires.